Rats and noise are one thing — but turning a neighborhood playground into a hangout for construction workers is just too much, say a band of Brooklyn neighbors near the rapidly rising Barclays Center arena.

The burly, foul-mouthed workers have virtually turned the children’s oasis into their own turf – lounging on benches, smoking cigarettes and then harassing neighbors who complain, residents told The Post.

The invasion has scared off many Park Slope and Prospect Heights parents and nannies, who say they had taken children to the Dean Street public playground between Sixth and Carlton avenues for years but now feel too intimidated to go back.

“It’s our neighborhood amenity, and now we feel like we can’t even go there anymore. They curse and have no respect,” said a 40-year-old mother who lives a block away with her 7-year-old daughter.

Other neighbors complain that the workers congregate on local stoops as well.

Peter Krashes, president of the Dean Street Block Association, said the neighborhood wouldn’t be overrun with construction workers if arena developer Forest City Ratner had provided a lounge area for their breaks.

Krashes also said the problems at the playground will “only get worse” once the 18,200-seat future home of the Nets opens Sept. 28 and thousands of patrons begin passing by it regularly.

An enterprising resident last week took photos of three workers hanging out at the Dean Street Playground sitting on benches and smoking cigarettes with kids playing nearby.

City law prohibits smoking in parks and also bars visiting children’s playgrounds without being accompanied by a youth. These rules are others outlined in a large sign at the 1.3-acre playground’s entrance.

The 56-year-old photographer, who declined to give his name because he claims he’s been both ”threatened and assaulted by” some of the workers, posted the photos on blog set up by arena opponents called Atlantic Yards Watch.

The blog regularly documents arena construction problems — such a dust, rats and noise issues. In January, it even posted video of construction workers ripping down a “No Standing” parking sign on Pacific Street, so they could park there and avoid tickets.

Civic leaders have asked the developer to station a security guard at the playground but to no avail.

A Forest City Ratner spokesman said the firm has “discussed” the playground “issue” with arena contractor Hunt Construction, the NYPD and the Mayor’s Office, adding police “should be notified” and potentially issue summonses if anyone is breaking the law.

However, residents say calling the cops has been ineffective because they generally can’t get there quick enough to catch the workers in the act.

The playground is just around the corner from the 78th Precinct on Sixth Avenue, but cops there aren’t responsible for it because it technically falls within the boundaries of the 77th Precinct — located 2.5 miles away in Crown Heights.

The NYPD is in the process of re-evaluating its precinct boundaries to best serve the arena, with the 78th Precinct expected to be assigned to maintain order there.